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A289554
Numbers that are the product of two distinct composite numbers (A002808).
1
24, 32, 36, 40, 48, 54, 56, 60, 64, 72, 80, 84, 88, 90, 96, 100, 104, 108, 112, 120, 126, 128, 132, 135, 136, 140, 144, 150, 152, 156, 160, 162, 168, 176, 180, 184, 189, 192, 196, 198, 200, 204, 208, 210, 216, 220, 224, 225, 228, 232, 234, 240, 243, 248, 250
OFFSET
1,1
EXAMPLE
Number 24 is in the sequence because 24 = 4 * 6.
PROG
(Magma) [n: n in [1..1000] | (#PrimeDivisors(n) eq 1 and NumberOfDivisors(n) ge 6) or (#PrimeDivisors(n) eq 2 and NumberOfDivisors(n) ge 8) or (#PrimeDivisors(n) ge 3 and NumberOfDivisors(n) ge 12) or (#PrimeDivisors(n) ge 4)]
CROSSREFS
Complement of A289555.
Cf. A006881 (with two distinct primes), A002808 (with two distinct nonprimes), A167171 (with two distinct noncomposites).
Sequence in context: A337055 A064673 A034782 * A334589 A334936 A102374
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jul 07 2017
STATUS
approved